Bed bugs are nocturnal insects that feed only on blood, mainly on the blood of humans. Bed bugs will suck blood from other animals, such as domestic pets, as well as pests such as birds and bats. They live in loose groups or individually and have a tendency to occupy cracks and crevices or other similar harborages. Bed bugs are stimulated to seek a host most likely by vibrations, body heat, and CO2 vapors. An inseminated adult female bed bug requires a blood meal within five days either before or after insemination for egg laying to occur. Once fed and inseminated, the female bed bug locates a suitable environment and deposits small, whitish eggs, which are attached with a cement-like material to surfaces in the cracks and crevices where they hide. Eggs can be found in caches in protected areas as well as individually in open spaces. Females typically lay 2-3 eggs per day and can lay 200 to 500 eggs in their lifespan. Under appropriate temperatures, eggs hatch after approximately 10 days but may be viable for as long as 28 days before hatching. Bed bug nymphs molt 5 times before reaching adulthood and require a blood meal prior to each molt. Adults can live without a meal for several months (in some reports, for more than a year) and nymphs for up to four months without feeding.
The time for development of each instar is dependant upon and available food source (host), temperature and humidity. With an available host, the ideal environment for development is 83° F. to 90° F. with 75% to 80% relative humidity. Under these conditions, all five nymph stages can be completed and sexual maturity reached in approximately 45-60 days. There is potential for 3-4 generations per year to be produced.
During the nymphal development stages, bed bugs may feed as frequently as once a day and usually feed at night when people are asleep; however, they will seek blood meals during the day under subdued or low light situations. It takes 3 to 12 minutes to feed to engorgement. To feed, the proboscis (piercing mouthpart) penetrates the skin and a feeding tube within the proboscis is extended and attached to a capillary. The person or animal being fed upon typically does not feel the penetration of the skin. The bed bug injects an anticoagulant into the wound to facilitate feeding. During the night, the insect may feed at several different points along the body before becoming fully engorged. Feeding is most often done horizontally across skin of the host as the insect travels along the sheets or other bedding. Bed bugs rest between feedings in protected areas near the location of a host awaiting a stimulus to signal them to seek their next meal. Under consistent moderate room temperatures and an adequate food supply bed bugs will live to 316 days. Low temperatures and/or an inconsistent food supply can actually extend the life span of stressed bed bugs up to 1 years as their metabolism slows (hibernation) and then returns to normal as temperatures rise or a host becomes available.
Bed bugs are of particular concern in the hospitality industry. A hotel's reputation for service and cleanliness is the driving factor in their quality rating and booking of room space. Therefore, bed bugs can be devastating to the hotel's reputation and create an immediate negative financial impact. While sanitation can play a role in the level of difficulty controlling a bed bug infestation, it has little to do with whether or not a customer may get them in the first place. Even so, the presence of bed bugs in a room is generally perceived by the public as an indication of improper sanitation and poor cleanliness.
Over the years, many techniques have been proposed for eliminating and preventing crawling insect pests such as cockroaches and ants in homes and businesses. These techniques focus on the minimal application of pesticides and placement of products in areas that humans and pets cannot come into contact with them. Unfortunately, these modern techniques have proven to be very ineffective against the common bed bug. Being blood feeders, bed bugs are not attracted to any current formulated baits, and currently there are no synthetic pheromones that could be used as attractants to traps, which further reduces the treatment strategies and options available to the modern pest management professional. The piercing mouthpart does not enable bed bugs to groom themselves or each other, which can limit effectiveness of dust formulations.
U.S. Pat. No. 6,141,901 discloses one prior art technique treating pests, including insects. The technique of this patent involves pumping heated outside air into the treatment zone (e.g., a structure) for a period of time. The outside air is heated to at least 200° F. and pumped into the structure until the temperature inside the structures rises, preferably at a rate of 10° F. per hour, until the temperature inside the structure reaches the lethal temperature, which, according to the patent, is usually about 120° F. to 130° F. for most pests.
U.S. Pat. No. 6,588,140 discloses another prior art technique for treating articles for pest infestation. In this patent, the articles to be treated are placed in an enclosure, which envelopes the articles. The enclosure is then sealed with a flexible, heat-resistant material, and hot air is pumped into the enclosure.
U.S. Pat. No. 6,327,812 discloses a process for killing organisms and removing toxins in an enclosure. In the process of this patent, temperature-sensing probes are installed within the enclosure. Hot air, produced by a heater external to the enclosure, is then introduced into the enclosure through one or more ingress ducts until the temperature within the enclosure reaches about 120° F.
Published U.S. patent application Pub. No. 2005/0220662 discloses a process for killing organisms, including bed bugs, in a room of a multi-room building. According to this published application, a heater is placed within the room of the building and heat sensitive articles within the room are removed. In addition, a number of temperature-sensing probes are positioned in the room. The heater then heats the ambient air within the room to a predetermined temperature, as measured by the temperature-sensing probes, of between 100° F. and 400° F.